Have you ever seen those drawings from other angles? They are extremly distorted and large. My suggestion to you would be to take a drawing and grid it out in a receeding perspective manor, then warp it so that it only works when viewed from one spesific angle.

Photoshop actually has tools that will distort an image this way. Once you begin to understand how things need to bend and warp and from what angle it needs you be viewed you will be a bit closer to being able to do this stuff.